OBD2 Fault Code Library

Free lookup for thousands of OBD2 trouble codes: filter by family, read short meanings, and open deeper articles. Desktop ELM327 scanner with live data and AI guidance.

OBD2 symptoms

Look up diagnostic trouble codes by what the car is doing: misfire, overheating, rough idle, a check engine light, and other common symptoms.

• Engine misfire
• Engine overheating
• Rough idle
• Check engine light
• Poor fuel economy
• Hard starting
• Engine stalling
• Catalytic converter efficiency
• Oxygen sensor fault
• EVAP leak
• Thermostat not reaching temperature
• Lean air-fuel mixture
• Rich air-fuel mixture
• EGR flow fault
• Engine knock
• Charging system
• Throttle position
• Mass airflow sensor
• Turbo underboost
• Coolant temperature sensor
• Transmission fault

• P2053 — Reductant Injection Valve Circuit/Open Bank 1 Unit 2 (P2053): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by faulty sensor or actuator of the affected circuit, poor ground connection, open or shorted wiring in the circuit.
• P2054 — Reductant Injection Valve Circuit Low Bank 1 Unit 2 (P2054): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by corroded, loose or damaged connector, control module driver fault, faulty sensor or actuator of the affected circuit.
• P2055 — Reductant Injection Valve Circuit High Bank 1 Unit 2 (P2055): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, open or shorted wiring in the circuit, control module driver fault.
• P2056 — OBD2 code P2056 flags a problem with the sensor and actuator circuits (reductant injection valve circuit/open bank 2 unit 2). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, open or shorted wiring in the circuit, control module driver fault.
• P2057 — Reductant Injection Valve Circuit Low Bank 2 Unit 2 (P2057): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, corroded, loose or damaged connector, control module driver fault.
• P2058 — OBD2 code P2058 flags a problem with the sensor and actuator circuits (reductant injection valve circuit high bank 2 unit 2). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• P2059 — P2059 — Reductant Injection Air Pump Control Circuit/Open. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: blown fuse feeding the circuit, open or shorted wiring in the circuit, poor ground connection.
• P205A — P205A — Reductant Tank Temperature Sensor Circuit. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, poor ground connection, faulty sensor or actuator of the affected circuit.
• P205B — OBD2 code P205B flags a problem with the sensor and actuator circuits (reductant tank temperature sensor circuit range/performance). The car is usually drivable while you plan the repair. Common culprits: faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector, blown fuse feeding the circuit.
• P205C — OBD2 code P205C flags a problem with the sensor and actuator circuits (reductant tank temperature sensor circuit low). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, open or shorted wiring in the circuit, control module driver fault.
• P205D — OBD2 code P205D flags a problem with the sensor and actuator circuits (reductant tank temperature sensor circuit high). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector.
• P205E — Reductant Tank Temperature Sensor Circuit Intermittent/Erratic (P205E): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• P205F — Reductant System Performance Bank 2 (P205F): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, control module driver fault, poor ground connection.
• P2060 — P2060 — Reductant Injection Air Pump Control Circuit Low. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: open or shorted wiring in the circuit, blown fuse feeding the circuit, corroded, loose or damaged connector.
• P2061 — P2061 — Reductant Injection Air Pump Control Circuit High. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, blown fuse feeding the circuit, open or shorted wiring in the circuit.
• P2062 — P2062 — Reductant/Regeneration Supply Control Circuit/Open. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, blown fuse feeding the circuit, open or shorted wiring in the circuit.
• P2063 — OBD2 code P2063 flags a problem with the sensor and actuator circuits (reductant/regeneration supply control circuit low). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, faulty sensor or actuator of the affected circuit, poor ground connection.
• P2064 — OBD2 code P2064 flags a problem with the sensor and actuator circuits (reductant/regeneration supply control circuit high). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• P2066 — P2066 — Fuel Level Sensor "B" Circuit Performance. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: faulty fuel pressure regulator, faulty fuel rail pressure sensor or wiring, clogged or leaking fuel injectors.
• P2067 — P2067 — Fuel Level Sensor "B" Circuit Low. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: weak fuel pump or clogged fuel filter, faulty fuel rail pressure sensor or wiring, faulty fuel pressure regulator.
• P2068 — Fuel Level Sensor "B" Circuit High (P2068): a powertrain (engine/transmission) fault affecting the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Most often caused by vacuum or intake leaks skewing the mixture, clogged or leaking fuel injectors, contaminated or incorrect fuel.
• P2069 — P2069 — Fuel Level Sensor "B" Circuit Intermittent. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: faulty fuel rail pressure sensor or wiring, vacuum or intake leaks skewing the mixture, weak fuel pump or clogged fuel filter.
• P206A — OBD2 code P206A flags a problem with the sensor and actuator circuits (reductant quality sensor circuit). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, open or shorted wiring in the circuit, corroded, loose or damaged connector.
• P206B — OBD2 code P206B flags a problem with the sensor and actuator circuits (reductant quality sensor circuit range/performance). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit, poor ground connection.